1. Meaning and Usage
"既然...就..." (jìrán... jiù...) is a conjunction structure used to express a logical consequence or decision based on an established premise, reason, or fact. It means "Since/Given that [premise], then [consequence/conclusion/suggestion]."
既然 introduces the premise, which is usually a known fact, an accepted situation, or a reason that has already been stated or is understood. 就 introduces the logical conclusion, action, decision, or suggestion that follows from the premise. It signifies "then," "in that case," or "accordingly."
This structure emphasizes that the consequence is a natural or necessary outcome once the premise is accepted.
2. Formulas and Examples
Case 1: Expressing a logical consequence or conclusion based on an accepted premise. This is the most common usage, where 既然 introduces a known fact, and 就 introduces what logically follows from it.
$$既然 + [Premise/Known Fact], (那/那么) 就 + [Logical Consequence/Conclusion].$$ (Note: 那 (nà) or 那么 (nàme) are optional but often used to reinforce the "then" aspect.)
既然你不想去，那就算了吧。 Jìrán nǐ bù xiǎng qù, nà jiù suànle ba. Since you don't want to go, then let's just forget about it.
既然他已经道歉了，我们就原谅他吧。 Jìrán tā yǐjīng dàoqiànle, wǒmen jiù yuánliàng tā ba. Since he has already apologized, then let's forgive him.
既然你都知道了，我就没什么好隐瞒的了。 Jìrán nǐ dōu zhīdàole, wǒ jiù méi shénme hǎo yǐnmán de le. Since you already know everything, then I have nothing left to hide.
Case 2: Giving a suggestion or making a decision based on a current situation or premise. Here, the consequence is often an action to be taken or a suggestion for what to do.
$$既然 + [Current Situation/Premise], (那/那么) 就 + [Suggestion/Decision/Action].$$
既然下雨了，我们就别去公园了。 Jìrán xiàyǔ le, wǒmen jiù bié qù gōngyuán le. Since it's raining, then let's not go to the park.
既然来都来了，就多玩一会儿吧。 Jìrán lái dōu láile, jiù duō wán yīhuìr ba. Since we've already come all this way, then let's play a bit longer.
既然你有时间，那就帮我一个忙吧。 Jìrán nǐ yǒu shíjiān, nà jiù bāng wǒ yīgè máng ba. Since you have time, then please help me out.
3. Essential HSK Tips & Common Mistakes
Don't forget 就 : While in very casual speech you might occasionally hear 既然 used alone, in formal writing and HSK exams, 既然 nearly always requires 就 (or 那/那么 就) to complete the structure. Omitting 就 can make the sentence sound incomplete or grammatically incorrect.
- Incorrect: 既然你累了，休息一下。
- Correct:
既然你累了，就休息一下吧。 Jìrán nǐ lèile, jiù xiūxí yīxià ba. Since you're tired, then take a rest.
就 vs. 所以 (suǒyǐ) : Although both can introduce a consequence, they are not interchangeable with 既然.
- 既然...就... emphasizes a logical deduction, a decision, or a suggestion based on an already known or accepted premise. The premise often implies an obligation or a natural flow to the consequence.
- 因为...所以... (yīnwèi... suǒyǐ...) emphasizes a direct cause-and-effect relationship. "Because X, therefore Y."
Consider the nuance:
因为他生病了，所以没来上班。 Yīnwèi tā shēngbìng le, suǒyǐ méi lái shàngbān. Because he was sick, therefore he didn't come to work. (Simple cause-effect)
既然他生病了，我们就别去打扰他了。 Jìrán tā shēngbìng le, wǒmen jiù bié qù dǎrǎo tā le. Since he is sick, then let's not go bother him. (Decision based on the known fact)
The premise with 既然 should be a known or accepted fact/situation. 既然 is used when the reason is not new information, but rather a basis for moving forward. This makes the consequence seem more natural or even obligatory.
既然你已经决定了，那我就支持你。 Jìrán nǐ yǐjīng juédìngle, nà wǒ jiù zhīchí nǐ. Since you've already made your decision, then I will support you. (Here, "you've made your decision" is presented as an established fact.)
Placement of 既然 : 既然 always comes at the beginning of the first clause, introducing the premise. The subject of the second clause (the consequence) can be the same as or different from the first.
既然我来了，我就要好好学习。 Jìrán wǒ láile, wǒ jiù yào hǎohǎo xuéxí. Since I've come, then I must study hard. (Same subject: 我)
既然时间不早了，我们就回家吧。 Jìrán shíjiān bù zǎole, wǒmen jiù huí jiā ba. Since it's getting late, then let's go home. (Different subjects: 时间 and 我们)